The invention relates to a method and apparatus for attaching dentures.
It is known to replace missing teeth in patients by implanting fixtures in the jawbone. In order to make the anchoring of the fixtures permanent, a number of requirements have to be met, including factors connected with the selection of materials and surgical technique. Fixtures in the form of screws are anchored in the jawbone by surgery and permitted to become integrated with bone tissue, a process known as osseointegration. The process of osseointegration is a healing process extending over a certain period of time.
The mounting of dental fixtures requires a tremendous amount of effort, resulting in relatively high costs for reconstruction of entire jaws. In addition, for each patient, the total time needed for reconstruction is prolonged. Therefore, it is desirable to reduce costs for reconstruction of entire jaws or for prosthetically reconstructing a continuous part of a row of teeth by application of user-friendly solutions aimed at reducing the time and work for implanting and mounting dental fixtures.
The present invention provides a simplified method for the fabrication of an implant supported fixed or removable dental prosthesis. It can be used to assist in the treatment of a totally or a partially edentulous patient. It can also be used with a prefabricated bar and clip apparatus for retaining an over-denture. The invention can be used in coordination with all root form implant designs and common or custom-made rotary instruments. The invention includes a base plate formed to correspond with the shape of the edentulous residual ridge of a specific patient. The base plate includes a large aperture. When the base plate is positioned on the ridge of the patient the aperture receives a jig bushing for guiding a rotary tool such as a drill bit or tapping device. The jig bushing can include multiple apertures.
The invention also provides a method for making the base plate. A casting of the patient""s residual ridge can be created. A jig bushing can be positioned on the casting at a desired position. A supportive material can be used around the jig bushing on the casting and a formable material can be dispensed in the space formed between the jig bushing and the outline of the adjoining edentulous residual ridge or teeth. The dispensed material can harden to form the base plate. In order to maintain the position of the jig bushing relative to the casting as the formable material is dispensed, a bore can be drilled through one or more of the apertures in the jig bushing, into the casting, and a stabilizing pin can be inserted in the bore.
The invention also provides a method of using the base plate to perform an operation with respect to the patient""s residual ridge. The base plate is formed to the shape corresponding to the ridge and any other surrounding structures as deemed necessary for stability and is engaged on the ridge. The engagement of the base plate with the ridge can be enhanced by positioning a rubber block between the base plate and the patient""s opposing jaw, by action of a technical surgical assistant to hold the base plate in place or by drilling a bore through the base plate and into the patient""s residual ridge and inserting a bone screw or nail. When the base plate is appropriately engaged with the patient""s residual ridge, an operation can be performed. The operation can be a drilling or tapping or wedging operation.
The invention also includes a method and apparatus for drilling a bore of predetermined depth and direction into the patient""s residual ridge at any position corresponding to an aperture in the jig bushing held by the base plate. The drilling apparatus can receive a plurality of different rotary tools for performing various operations with respect to the ridge. The depth that the drill travels into the patient""s ridge can be controlled by a stopping means. The stopping means can include an annular recess formed along the length of a drill bit adaptor of the drilling means and an E-ring element receivable into the recess. When the plurality of bores are to be drilled into the patient""s ridge, a stabilizing pin can be inserted into the bore created by the first drilling operation to enhance the engagement of the base plate with the ridge.
The invention also provides a method for mounting a dental prosthesis to the patient""s residual ridge. After the bores have been drilled and taped into the patient""s ridge an implant can be inserted into the bore. An extension adaptor can be mounted on the end of the implant. This extension fits to the end of the implant and penetrates through the depth of the adjacent mucosa extending into the mouth. The length of the extension corresponds to the depth of the placement of the implant and the desired height in the mouth. When a plurality of implants are so placed and connected with related extensions the implants will form an array of receiving terminal ends in the mouth. To these terminal ends, a top plate can be connected for use as a framework for a dental prosthesis.
The invention also includes a method for customizing a pre-machined top plate prosthodontic connector to be fastened to the receiving ends of the implants. A casting of the edentulous residual ridge with the plurality of implants and associated terminal ends for receiving the top plate can be created. A top plate can be positioned on the represented terminal ends and the plate can be custom modified with the attachment of appropriate dental materials to form a custom prosthesis.
Other applications of the present invention will become apparent to those skilled in the art when the following description of the best mode contemplated for practicing the invention is read in conjunction with the accompanying drawings.